TypeExtensions

Table of contents

• General info
• Technologies
• Setup
• Usage
• Contributors
• Links

General info

JejeQL is a tool that can translate a query into a predicate and filter data.

Technologies

• Node.js
• Typescript

Setup

npm install @jeje-devs/type-extensions

Usage

First of all, you need to call the extend() method. Otherwise the extensions won't work

import { extend } from '@jeje-devs/type-extensions';

extend();

String extensions

• toNumberOrNull

Converts a string to number if possible. Otherwise gives null

const numberValue = '45'.toNumberOrNull();
// returns 45

• toBooleanOrNull

Converts a string to boolean if possible. Otherwise gives null. The accepted values can be 'true', '1', 'false', '0'

const booleanValue = 'true'.toBooleanOrNull();
// returns true

• isValidUrl

Indicates whether a string is a basic url or not

const isValid = 'http://localhost:8080/api/test'.isValidUrl();
// returns true

• toFilename

Converts a string url to a filename

const filename = 'http://localhost:8080/img/my_image.jpg?h=45712'.toBooleanOrNull();
// returns 'my_image.jpg'

• isAlphanumeric

Indicates whether a string is alphanumeric or not. This means that it contains only numbers

const isAlphanumeric = '4526756'.isAlphanumeric();
// returns true

Array extensions

• sum

Sums all items of an array

const sum = [7, 5, -6, 2].sum();
// returns 8

• indexWhere

Gives the first index found when the given predicate matches

const index = ['a', 'f', 'z', 'u'].indexWhere(x => x === 'z');
// returns 2

• shuffle

Shuffles an array

const shuffleArray = [7, 5, -6, 2].shuffle();

• parallel

Asynchronously Runs an action method for each array element

await [{ name: 'John' }, { name: 'Mary' }, { name: 'Paul' }].parallel(async (item, index) =>
{
    // Do asynchronous stuff;
    item.name = `Hello ${item.name}!`;
})

• groupBy

Groups an array by a given key

const array = [{ personId: 1, paid: 10.50 }, { personId: 1, paid: 53.20 }, { personId: 2, paid: 12.99 }]
    .groupBy(x => x.personId);
/*
returns [
    { key: 1, values: [{ personId: 1, paid: 10.50 }, { personId: 1, paid: 53.20 }] },
    { key: 2, values: [{ personId: 2, paid: 12.99 }] }
]
*/

• distinct

Removes all duplicates in an array

const distinctArray = [1, 2, 1, 3, 1, 4].distinct();
// returns [1, 2, 3, 4]

• filterNil

Removes all 'null' or 'undefined' items from an array

const filtered = ['foo', null, 'bar', undefined, 'baz'].filterNil();
// returns ['foo', 'bar', 'baz']

Date extensions

• toDateISOString

Gives a date string without time, as ISO

const date = new Date(2023, 5, 30).toDateISOString();
// returns 2023-06-30

• getRangeTo

Gives an array of dates from start to end parameters

const dates = new Date(2023, 0, 1).getRangeTo(2023, 0, 5);
// returns as dates [2023-01-01, 2023-01-02, 2023-01-03, 2023-01-04, 2023-01-05]

• addYears

Add years to a date

const date = new Date(2023, 5, 30).addYears(2);
// returns as date 2025-06-30

Contributors

• Jérémie Primas

Links

• npm
• GitHub